Dequan McKethan was charged with murder Monday in the death of a Norwich man whose body was found Sept. 25 at a Bozrah ballfield.

Darius Bishop, 27, of Norwich, was shot a single time in the head, police said in an arrest warrant in the case. Police said they found a .22-caliber bullet casing near his body.

McKethan, 34, of 61 Summit St., who has been in custody since Sept. 27 on gun and drug charges, appeared Monday in Norwich Superior Court. He is being held on a $1 million bond in the murder case and is expected to appear Jan. 7 in New London Superior Court.

Testing by the state crime lab showed the casing has markings that were produced by the .22-caliber Beretta handgun police found in McKethan’s possession when they arrested him, the arrest warrant says.

The bullet that killed Bishop, although .22-caliber, could not be positively matched, police said.

McKethan’s DNA was found on the trigger and magazine, police said, but not on the gun’s slide or grip.

Police also linked McKethan and Bishop through cellphone records. The two made several calls and exchanged text messages to each other on the night of the killing, police said.

The locations of the cellphones were shown to be together during the night at sites in Norwich, Griswold and the place where Bishop’s body was found the following morning, the Charles L. Long Sports Complex in Bozrah. Police said they have not found Bishop’s cellphone.

A neighbor of the sports complex said he heard a shot between 2:10 a.m. and 2:30 a.m., police said.

Police pulled over McKethan’s car Sept. 27 on Mechanic Street in Norwich and found the gun and a small quantity of cocaine, police said.

Questioned by police after his Sept. 27 arrest, McKethan admitted buying pot regularly from Bishop, police said. He said he was shocked at Bishop’s death and that he was home with his girlfriend and their daughter. Police said McKethan could not explain the records of the calls to and from Bishop and said he didn’t speak to Bishop that night.

McKethan said he had let a friend named “D” borrow his car, and that the gun must belong to D.